Method of making a plastic building wall fin unit

ABSTRACT

A PREFABRICATED PLASTIC BUILDING WALL FIN UNIT COMPRISING A GENERALLY U-SHAPED REINFORCED PLASTIC SHELL HAVING BRACKET MEANS FOR SECURING THE FIN UNIT TO A BUILDING WALL. FIREPROOFING MATERIAL MAY BE APPLIED TO THE INTERIOR SURFACE OF THE SHELL. A FORAMINOUS REINFORCEMENT   MAY BE PARTIALLY EMBEDDED IN THE SHELL TO PROVIDE POSITIVE CONNECTION FOR THE FIREPROOFING MATERIAL AND TO PROVIDE STRUCTURAL REINFORCEMENT FOR THE SHELL.

K. A. SCHAFER 3,591,437

METHOD OF MAKING A PLASTIC BUILDING WALL FIN UNIT July 6, 1971 Filed July 1, 1968 RR Z M 4 i "H N M K United States Patent 3,591,437 METHOD OF MAKING A PLASTIC BUILDING WALL FIN UNIT Kenneth A. Schafer, Pittsburgh, Pa., assignor to H. H. Robertson Company, Pittsburgh, Pa. Filed July 1, 1968, Ser. No. 741,562 Int. Cl. B29c 19/00 U.S. Cl. 156--245 4 Claims ABSTRACT OF THE DISCLOSURE A prefabricated plastic building wall fin unit comprising a generally U-shaped reinforced plastic shell having bracket means for securing the fin unit to a building wall. Fireproofing material may be applied to the interior surface of the shell. A foraminous reinforcement may be partially embedded in the shell to provide positive connection for the fireproofing material and to provide structural reinforcement for the shell.

BACKGROUND OF THE INVENTION (1) Field of the invention This invention relates to a prefabricated plastic building wall fin unit, and method of making the same and more particularly to a fin unit adapted for erection with a building wall for service as an architectural columnlike building feature element.

(2) Description of the prior art Building wall fins are used extensively in new building structures. The wall fins project outwardly from the exterior wall of the building and serve as prominent feature elements. The wall fins interrupt the large expanse of essentially fiat wall areas and render these wall areas more attractive. The wall fins normally are non-load bearing elements.

In the past, the building wall fins have comprised precast concrete elements having a white appearance.

The use of pre-cast concrete wall fins has many disadvantages. The weight of pre-cast concrete wall fins is great. For example, a recently erected building incoporates a plurality of 26 feet long, pre-cast concrete wall fins having a weight per foot of length of fin of 770 pounds or a gross weight of tons each. In a proposed building, the pre-cast concrete wall fins would have a weight per foot of length of fin of 300 pounds. The great weight of the pre-cast concrete wall fins adds considerably to the structural steel tonnage of the building frame and to the foundation costs. Additionally, complicated wall fin-to-spandrel beam connections are required and expensive erection procedures are necessary. The use of pre-cast concrete in fins is not an efficient use of materials since the wall fins are non-load bearing elements.

SUMMARY OF THE INVENTION The principal object of this invention is to provide a building wall fin unit which is relatively light in weight and which may be produced in a variety of architectural configurations.

Another object of this invention is to provide a building wall fin which does not have the disadvantages of the prior art pre-cast concrete wall fins.

A further object of this invention is to provide a method of making a plastic building wall fin unit.

The present invention provides a prefabricated building wall fin comprising a generally U-shaped reinforced plastic shell having spaced-apart inboard longitudinal edges. A lath-like reinforcement, such as an expanded metal screen, may be embedded in the interior surface of the reinforced plastic shell such that surfaces thereof project from the interior of the shell. A lightweight fireproofing material may be provided on the interior surface of the reinforced plastic shell and is mechanically secured thereto by the lath-like reinforcement. Bracket means having one end secured to the reinforced plastic shell project at the other end away from the inboard longitudinal edges of the reinforced plastic shell and adapt the building wall fin unit for erection to a building structural framework.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a building provided with building wall fin units of this invention;

FIG. 2 is a fragmentary isometric view illustrating the present building wall fin unit and alternative bracket means adapting the fin unit for erection to a building wall;

FIG. 3 is a cross-sectional view, on an enlarged scale, taken along the line 33 of FIG. 2;

FIGS. 4 and 5 are fragmentary side views illustrating typical structures for securing the present building wall fin unit to a building framework;

FIG. 6 is an exploded side view, in cross-section, illustrating a butt joint between two vertically aligned fin units of this invention;

FIG. 7 is an exploded side view, in cross-section, illustrating an overlapped connection between two verti cally aligned fin units of this invention;

FIGS. 8-11, inclusive, are transverse cross-sectional views, illustrating alternative configurations of the pres ent building wall fin unit;

FIG. 12 is a schematic end view of the present building wall fin unit, illustrating various dimensions; and

FIG. 13 is a fragmentary isometric view of mold apparatus employed in the manufacture of the present building wall fin unit.

DESCRIPTION OF THE PREFERRED EMBODIMENT(S) FIG. 1 illustrates a building 20 having exterior walls 22 and a roof 23. Each of the exterior walls 22 is pro vided with a plurality of building wall fin units 24. The wall fin units project outwardly from the exterior Wall 22 and may extend from ground level to the level of the roof 23. The wall fin units 24 are prominent feature elements which interrupt the large expanse of flat area which the exterior walls 22 would present in the absence of the wall fin units 24.

Referring to FIG. 2, the present building wall fin unit 24 comprises a generally U-shaped shell 26 fabricated from reinforced plastic and including a base 28 and tWo legs 30 terminating in spaced-apart inboard longitudinal edges 32. The building wall fin unit 24 is provided with bracket means 34, such as plate members 36 which are secured to the shell 26 and have terminal mounting portions 38 which are usually coplanar. Alternatively, the building wall fin unit 24 may, instead, be provided with bracket means 34, such as structural angles 40, shown in dotted outline, which are secured to the shell 26.

If desired, a lightweight fireproofing material 42 may be applied to the inner surfaces of the web 28 and the legs 30 of the building wall fin unit 24. Lightweight fireproofing materials suitable for use in the present invention include vermiculite, sprayed fibrous materials, foamed gypsum, and the like.

Referring to FIG. 3, the shell 26 comprises a cured thermoset resinous mass 44 which engulfs and surrounds reinforcing fibers 46. If desired, a weather resistant film 48 may be secured to an exterior surface 49 of the resinous mass 44 during fabrication of the shell 26. The

weather resistant film 48 may comprise polyvinyl fluoride having a thickness in the range of from 1 to 5 mils. The film 48 constitutes the exposed surface of the building wall fin unit 24.

Additional reinforcing means may be provided for reinforcing the shell 26. The additional reinforcing means may comprise lath material, such as an expanded metal screen 50. As can be seen in FIG. 3, the expanded metal screen 50 has surfaces 51 embedded in the resinous mass 44 and surfaces 53 projecting from the inner surface 52 of the resinous mass 44.

The lightweight fireproofing material 42 is applied to the inner surface 52 of the resinous mass 44 whereby the surfaces 53 of the expanded metal screen 50 comprise bonding and reinforcing means interposed between the lightweight fireproofing material 42 and the reinforced plastic shell 26 for mechanically bonding the fireproofing material 42 to the shell 26 and for additionally reinforcing the shell 26. The expanded metal screen 50 has surfaces 51 embedded in the reinforced plastic shell 26 and has surfaces 53 embedded in the fireproofing material 42.

The cured thermoset resinous mass 44 may comprise any suitable resinous composition including, unsaturated polyesters, epoxy and other thermosetting resins.

The reinforcing fibers 46 may comprise preformed mats of randomly oriented glass fibers. Alternatively, the reinforcing fibers may comprise short glass fibers such as provided by convention spray techniques wherein short glass fibers and a liquid polymerizable resinous composition are simultaneously sprayed onto surfaces of a pattern or mold. Examples of other suitable reinforcing fibers include synthetic organic fibers such as polyester or polyamide fibers and the like.

As shown in FIG. 4, the building wall fin unit 24 can be erected by securing the terminal mounting portions 38 of the plate members 36 to a vertical web 54 of a horizontal girt 56 by suitable fasteners 58.

As shown in FIG. 5, the building wall fin unit 24 can be erected by securing the structural angles 40 to one of the horizontal flanges 60 of the horizontal girt 56 by suitable fasteners 62.

Referring to FIG. 6, there is illustrated a butt joint between two building wall fin units 24A, 24B. Each of the building wall fin units 24A, 24B are provided with upper and lower flanges 64, 66, respectively, which extend inwardly of the shell 26. The lower flange 64 is provided with a bead 68 and the upper flange 66 is provided with a complementary groove 70. A sealant material 72 is provided in the complementary groove 70. The bead 68 and complementary groove 70 serve to maintain the building wall fin units 24A, 24B in vertically aligned relation. Moreover, engagement of the bead '68 with the sealant material 72 seals the butt joint between the building wall fin units 24A, 24B.

Referring to FIG. 7, there is illustrated two vertically aligned building wall fin units 24C, 24D positioned to be assembled in top-to-bottom overlapping relationship. In this arrangement, the shell 26 and the lightweight fireproofing material 42 are coterminating at their upper ends. The shell 26 has a flange portion 74 extending downwardly beyond the lightweight fireproofing material 42 at the bottom end of the fin unit 24C for a lapping distance indicated at 76. Additionally, the shell 26 is inwardly recessed as at 78 at the upper end of the fin unit 24C for a distance corresponding to the lapping distance 76. As shown in FIG. 7, the subjacent wall fin unit 24D is inwardly recessed at 98. The overall arrangement is such that the two building wall fin units 24C, 24D can be assembled in top-to-bottom overlapping relation.

Referring still to FIG. 7, the upper end of the fin unit 24C may be provided with a closure element 80 having a depending flange 82. When the closure element 80 is installed, the depending flange 82 engages the exterior surface of the shell 26 in the region of the recess 78.

The lower end of the fin unit 24D also may be pro- 4 vided with a closure element 84 having a peripheral flange 86. When the closure element 84 is installed, the peripheral flange 86 engages the interior surface of the flange portion 74.

The closure elements 80, 84 may be adhesively secured to the shells 26 by a suitable adhesive 88. The adhesive 88 may be applied, for example, to the inner surface of the depending flange 82 of the closure element 80, and to the exterior surface of the peripheral flange 86 of the closure element 84, as illustrated in FIG. 7. Suitable adhesives include asphalts, epoxy adhesives, polyurethane sealants, et cetera. Alternatively, the closure elements 80, 84 may be secured to the shell 26 by any suitable fastener elements.

The present building wall fin unit can be provided in the profile of FIG. 2 and other profiles, such as illustrated in FIGS. 81l, inclusive. The building wall fin units 90, 92, 94 and 96 of FIGS. 8-11, respectively, include a fiber reinforced plastic shell 26, lightweight fireproofing material 42, and expanded metal screen (not visible) securing the fireproofing material 42 to the shell 26, and bracket means 34.

EXAMPLE A comparison is presented between the wall fins of this invention and the presently available pre-cast concrete wall fins in the trapezoid profile shown in FIG. 12.

The wall fin dimensions indicated in FIG. 12 are summarized in Table A. It is to be noted that the pre-cast concrete wall fin has a solid trapezoidal profile whereas the wall fin on this invention has a generally U-shaped profile shown in FIG. 12. Accordingly, a pre-cast concrete wall fin has no counterpart dimension to the thicknesses T T or their sum.

1 Solid concrete.

A comparison of the weights of the wall fins in a typical building is given below in Table B.

TABLE 13 Pre-cast Wall fin unit concrete this Item wall fins invention Total linear feet" 64, 000 64, 000 Weight per linear to 300 1 10. 6 Gross weight, tons 9, 600 339 Building structural steel frame, tons 1 10, 000 9, 000

1 Based on the average density of the shell 26 material and of the fireproofing material 42. fin slncludes weight of structural steel frame required to support the wall As can be seen from Table B the gross weight of the present wall fin units is only 3.5 percent of the gross weight of the pre-cast concrete wall fins. Also, the present wal fin units permit a reduction of approximately 1,000 tons or 10 percent of the building structural steel framing which would be required in the typical building herein considered, if the pre-cast concrete Wall fins are used.

METHOD Referring to FIG. 13, there is illustrated a pattern or mold 98 for producing the wall fin unit 24 of FIG. 2. The pattern 98 has a trough-like configuration including a bottom wall 100, diverging side walls 102, 104 and end walls 106 (only one shown). The bottom wall 100 and the diverging side walls 102, 104 may have plain interior surfaces or may have interior surfaces which are textured to correspond with the texture of various materials, such as concrete, for example.

In accordance with one embodiment of the present method of making prefabricated plastic building wall fin units, the reinforcing fibers 46, in the form of preformed mats of randomly oriented reinforcing fibers, are applied to the interior surfaces of the walls 100, 102 and 104 of the pattern 98. A liquid thermosetting resinous composition is applied to the preformed mats in a quantity sufiicient to engulf and surround the same. The liquid thermosetting resinous composition is allowed to cure partially and thereafter, the lath material 50 is applied to the exposed sur faces of the partially cured thermosetting resinuous com position, such that the lath material 50 is partially embedded in the partially cured thermosetting resinous composition. The partially cured resinous composition, the preformed mats of randomly oriented reinforcing fibers and the lath material are retained in assembled relation within the pattern until the resinous composition has substantially completely cured.

After the thermosetting resinous composition has cured, a layer of lightweight fireproofing material (not shown) may be applied to the interior surfaces of the shell 26. The lightweight fireproofing material is mechanically bonded to the thermosetting resinous composition by embedment of the exposed portions of the lath material 50 in the fireproofing material.

In accordance with an alternative embodiment of the present method of making prefabricated plastic building wall fin units, the reinforcing fibers 46 and the liquid thermosetting resinous composition are applied simultaneously to the pattern 98 by conventional spraying techniques. In this instances, short lengths of reinforcing fibers are sprayed along with a stream of liquid thermosetting resinous composition against the pattern 98, whereby the resin-coated reinforcing fibers are arrayed in random orientation.

If desired, a film of weather resistant material, such as the film 48 (-FIG. 3) may be applied to the interior surfaces of the walls 100, 102 and 104 of the pattern 98 prior to the application of the reinforcing fibers 46 and the liquid thermosetting resinous composition. In this instance, the film also serves as a mold release agent.

The shell 26 may be formed from thermosetting resinous compositions of various colors. The resulting building wall fin may have a color which blends with the color of the building or may have a contrasting color to render the building wall fins more prominent. Furthermore, the thermosetting resinous composition may have a mottled color or pattern to produce a surface appearance in imitation of marble. An appearance simulating that of white concrete may be achieved by suitable white pigmentation of the plastic substance.

SUMMARY The present invention provides a building wall fin unit which is lightweight when compared with the prior art precast concrete wall fins; which may be produced in a variety of architectural configurations and in any of a variety of colors; which may be produced with a plain or a textured surface in imitation of marble, concrete or the like; and which does not have the many disadvantages of the prior art pre-cast concrete wall fins. The present invention also provides a novel method for making a building wall fin unit.

What is claimed is:

1. The method of making a building wall fin unit comprising the steps of:

applying reinforcing fibers to surfaces of a pattern;

applying a liquid thermosetting resinous composition to said reinforcing fibers to engulf and surround the same;

partially curing said thermosetting resinous composition; applying a lath material to the exposed surfaces of said partially cured thermosetting resinous composition such that said lath material has surfaces embedded in said partially cured thermosetting resinous composition and surfaces projecting therefrom; and

retaining said partially cured thermosetting resinous composition, said reinforcing fibers and the said lath material in assembled relation within said pattern until said partially cured resinous composition has substantially completely cured.

2. The method defined in claim 1 wherein said reinforcing fibers are applied as mats of randomly oriented glass fibers.

3. The method defined in claim 1 wherein said reinforcing fibers and said liquid thermosetting resinous composition are applied concurrently to surfaces of said pattern.

4. The method defined in claim 1 including the step of applying a layer of lightweight fireproofing material to said lath material and the said thermosetting resinous composition after said thermosetting resinous composition has substantially completely cured.

References Cited UNITED STATES PATENTS 2,826,521 3/1958 Robinson 156-300X 2,999,043 9/1961 Glynn 156300X 3,453,165 7/1969 Isbey et al. 156300X CARL D. QUARFORTH, Primary Examiner S. J. LECHERT, JR., Assistant Examiner US. Cl. X.R. 

